The present teachings relate to optical systems that can provide mixing of light as well as shaping of the mixed light, e.g., converging the mixed light to generate a narrow angular beam profile.
It is typically challenging to produce a narrow beam of light when using multi-chip LED (light emitting diode) sources, e.g., when using LED packages with 2 or more LED chips. For example, in some lighting applications in which individual LED chips are separated by a gap, or in which the LED chips emit different colors, a beam of light generated by mixing the light from the LED chips can exhibit a dark spot at its center and/or may exhibit poor color mixing, respectively.
Hence, there is a need for improved optical systems that can provide mixing of light emitted by one or a plurality of light sources and can shape the angular profile of the mixed light, and in particular, there is a need for improved systems that can mix light from light sources providing light of different colors.